Inserts (1974) [Harlene]: Dies of a heroin overdose (off-screen); her body is shown afterwards, wrapped in a sheet, when Bob Hoskins and Stephen Davies carry her out. (We only see her arm sticking out of the sheet.)

Invasion of the Body Snatchers(1978) [Nancy Bellicec]: Presumably replaced by an alien duplicate, shortly after the end of the movie; the movie ends with the duplicate Donald Sutherland pointing her out to the other pod-people. (Thanks to Christopher)

Alien (1979) [Lt. Lambert]: Killed (off-screen) by the alien; we only her her screams over the intercom after it corners her. Her dangling legs are shown afterwards when Sigourney Weaver discovers her.Guyana Tragedy: The Story of Jim Jones (The Mad Messiah) (1980) [Marceline 'Marcy' Jones]: Commits suicide by drinking poison during the cult's mass suicide. (Thanks to Robert)

The Witches of Eastwick (1987) [Felicia Alden]: Beaten to death (off-screen) with a fireplace poker by Richard Jenkins, after Jack Nicholson casts a spell causing her to vomit profusely. We only hear the blows from outside the house.

The Lottery(1996) [Maggie Dunbar]: Stoned to death by the townspeople after she is chosen in the "lottery." (Thanks to Utonium)

CSI: Rashomama(2006) [Diane Chase]: Dragged to death after Claire Coffee and Rheagan Wallace tie her to the back of her car, on top of having been impaled on the "arrow" of an archer statue by Amanda Seyfried. (Thanks to PortsGuy)